Re: [PATCH v3 09/14] media: platform: pxa_camera: add buffer sequencing

Robert Jarzmik
2016-08-15T13:27:01Z

Robert Jarzmik <robert.jarzmik@free.fr> writes:

> Add sequence numbers to completed buffers.
>
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> ---
> drivers/media/platform/soc_camera/pxa_camera.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/media/platform/soc_camera/pxa_camera.c b/drivers/media/platform/soc_camera/pxa_camera.c
> index d66443ac1f4d..8a65f126d091 100644
> --- a/drivers/media/platform/soc_camera/pxa_camera.c
> +++ b/drivers/media/platform/soc_camera/pxa_camera.c
> @@ -401,6 +402,7 @@ static void pxa_camera_start_capture(struct pxa_camera_dev *pcdev)
> unsigned long cicr0;
>
> dev_dbg(pcdev_to_dev(pcdev), "%s\n", __func__);
> + pcdev->buf_sequence = 0;

I'm not so sure this is the right place to reset the buffer sequence.

I've seen no documentation on the rules applicable to this sequence number:
- should it be reset if a "start streaming" operation occurs ?
- should it be reset if a streams stops by lack of video buffers queued ?
- should it be reset in queue_setup() like in other drivers ?

Or should it _never_ be reset and only be a monotonic raising number ?

Cheers.

--
Robert